Ninhydrin → Sodium 3,6-disulfonaphthylthiourea

Participants

Reaction Conditions

Reaction Steps

Solid sodium 3,6-Disulfonapthylisothiocyanate (200 mg; 0.51 mmol) was added to a solution of poly-L-lysine (15-30K) (50 mg) in a mixture of water (2 ml) and N,N-dimethyl-N-allylamine buffer (pH 9.5; 2 ml). The resulting mixture was heated under nitrogen at 53° C. for 3 hours, when a ninhydrin test was negative. The cooled mixture was filtered and the filtrate concentrated to give a brownish solid residue. The solid residue was redissolved in water and passed through a column of Amberlite IR 120(Na) and then concentrated. The crude product was purified by gel filtration (Sephadex LH20; water) and freeze dried to give sodium 3,6-disulfonaphthylthiourea terminated poly-L-lysine BRI6047 as a white fluffy solid (87 mg).

Provenance & Evidence